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Rails 3 - can't install pg gem
...pplications/Postgres.app/Contents/MacOS/bin:$PATH"
gem install pg should now work. (This is what worked for me.)
Note New versions path looks like:
/Applications/Postgres.app/Contents/Versions/<version>/bin
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How can I determine what font a browser is actually using to render some text?
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Per Wilfred Hughes' answer, Firefox now supports this natively. This article has more details.
This answer original referenced the "Font Finder" plugin, but only because it was from 4 years ago. The fact that old answers linger like this and the community can...
Summarizing multiple columns with dplyr? [duplicate]
...x. I have a data frame with different variables and one grouping variable. Now I want to calculate the mean for each column within each group, using dplyr in R.
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Bash continuation lines
... Thanks for your help, but while this does remove the spaces, they are now separate parameters (Bash is interpreting the spaces on the second line as a parameter separator) and are now only printed correctly because of the echo command.
– user880248
Sep 6 '...
What is an existential type?
...X they're saying: You can plug in whatever type you want, I don't need to know anything about the type to do my job, I'll only refer to it opaquely as X.
When someone defines an existential type ∃X they're saying: I'll use whatever type I want here; you wont know anything about the type, so you c...
What is a race condition?
...read scheduling algorithm can swap between threads at any time, you don't know the order in which the threads will attempt to access the shared data. Therefore, the result of the change in data is dependent on the thread scheduling algorithm, i.e. both threads are "racing" to access/change the data....
Choosing a Java Web Framework now? [closed]
...ng for. I can't really talk about (recent versions) of Flex and GWT but I know that Grails does have some fans.
Actually, I'd suggest to take a look at Matt Raible's presentations, he really did a great job at comparing web frameworks, showing their strengths and weakness, gathering facts and numb...
How to fix Error: “Could not find schema information for the attribute/element” by creating schema
...e- app.xsd which I saved to the root directory. The errors dissapeared but now i get a warning: "The global element 'configuration' has aleady been declared". Any idea on how to fix this?
– Brian McCarthy
Mar 15 '11 at 16:10
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What are bitwise shift (bit-shift) operators and how do they work?
..., you would use the following math:
memoryOffset = (row * 320) + column
Now, back in that day and age, speed was critical, so we would use bitshifts to do this operation.
However, 320 is not a power of two, so to get around this we have to find out what is a power of two that added together make...
How do you use bcrypt for hashing passwords in PHP?
Every now and then I hear the advice "Use bcrypt for storing passwords in PHP, bcrypt rules".
11 Answers
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